spandsp  0.0.6
private/hdlc.h
1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * private/hdlc.h
5  *
6  * Written by Steve Underwood <steveu@coppice.org>
7  *
8  * Copyright (C) 2003 Steve Underwood
9  *
10  * All rights reserved.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU Lesser General Public License version 2.1,
14  * as published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 #if !defined(_SPANDSP_PRIVATE_HDLC_H_)
27 #define _SPANDSP_PRIVATE_HDLC_H_
28 
29 /*!
30  HDLC receive descriptor. This contains all the state information for an HDLC receiver.
31  */
33 {
34  /*! 2 for CRC-16, 4 for CRC-32 */
35  int crc_bytes;
36  /*! \brief Maximum permitted frame length. */
37  size_t max_frame_len;
38  /*! \brief The callback routine called to process each good received frame. */
39  hdlc_frame_handler_t frame_handler;
40  /*! \brief An opaque parameter passed to the frame callback routine. */
42  /*! \brief The callback routine called to report status changes. */
43  modem_rx_status_func_t status_handler;
44  /*! \brief An opaque parameter passed to the status callback routine. */
46  /*! \brief TRUE if bad frames are to be reported. */
48  /*! \brief The number of consecutive flags which must be seen before framing is
49  declared OK. */
51  /*! \brief TRUE if framing OK has been announced. */
53  /*! \brief Number of consecutive flags seen so far. */
55 
56  /*! \brief The raw (stuffed) bit stream buffer. */
57  unsigned int raw_bit_stream;
58  /*! \brief The destuffed bit stream buffer. */
59  unsigned int byte_in_progress;
60  /*! \brief The current number of bits in byte_in_progress. */
61  int num_bits;
62  /*! \brief TRUE if in octet counting mode (e.g. for MTP). */
64  /*! \brief Octet count, to achieve the functionality needed for things
65  like MTP. */
67  /*! \brief The number of octets to be allowed between octet count reports. */
69 
70  /*! \brief Buffer for a frame in progress. */
71  uint8_t buffer[HDLC_MAXFRAME_LEN + 4];
72  /*! \brief Length of a frame in progress. */
73  size_t len;
74 
75  /*! \brief The number of bytes of good frames received (CRC not included). */
76  unsigned long int rx_bytes;
77  /*! \brief The number of good frames received. */
78  unsigned long int rx_frames;
79  /*! \brief The number of frames with CRC errors received. */
80  unsigned long int rx_crc_errors;
81  /*! \brief The number of too short and too long frames received. */
82  unsigned long int rx_length_errors;
83  /*! \brief The number of HDLC aborts received. */
84  unsigned long int rx_aborts;
85 };
86 
87 /*!
88  HDLC transmit descriptor. This contains all the state information for an
89  HDLC transmitter.
90  */
92 {
93  /*! 2 for CRC-16, 4 for CRC-32 */
94  int crc_bytes;
95  /*! \brief The callback routine called to indicate transmit underflow. */
96  hdlc_underflow_handler_t underflow_handler;
97  /*! \brief An opaque parameter passed to the callback routine. */
98  void *user_data;
99  /*! \brief The minimum flag octets to insert between frames. */
101  /*! \brief TRUE if frame creation works in progressive mode. */
103  /*! \brief Maximum permitted frame length. */
105 
106  /*! \brief The stuffed bit stream being created. */
108  /*! \brief The number of bits currently in octets_in_progress. */
109  int num_bits;
110  /*! \brief The currently rotated state of the flag octet. */
112  /*! \brief The number of flag octets to send for a timed burst of flags. */
114  /*! \brief The number of abort octets to send for a timed burst of aborts. */
116  /*! \brief TRUE if the next underflow of timed flag octets should be reported */
118 
119  /*! \brief The current message being transmitted, with its CRC attached. */
120  uint8_t buffer[HDLC_MAXFRAME_LEN + 4];
121  /*! \brief The length of the message in the buffer. */
122  size_t len;
123  /*! \brief The current send position within the buffer. */
124  size_t pos;
125  /*! \brief The running CRC, as data fills the frame buffer. */
126  uint32_t crc;
127 
128  /*! \brief The current byte being broken into bits for transmission. */
129  int byte;
130  /*! \brief The number of bits remaining in byte. */
131  int bits;
132 
133  /*! \brief TRUE if transmission should end on buffer underflow .*/
134  int tx_end;
135 };
136 
137 #endif
138 /*- End of file ------------------------------------------------------------*/
void * status_user_data
An opaque parameter passed to the status callback routine.
Definition: private/hdlc.h:45
int inter_frame_flags
The minimum flag octets to insert between frames.
Definition: private/hdlc.h:100
int crc_bytes
Definition: private/hdlc.h:35
int byte
The current byte being broken into bits for transmission.
Definition: private/hdlc.h:129
size_t max_frame_len
Maximum permitted frame length.
Definition: private/hdlc.h:104
int framing_ok_threshold
The number of consecutive flags which must be seen before framing is declared OK. ...
Definition: private/hdlc.h:50
void * user_data
An opaque parameter passed to the callback routine.
Definition: private/hdlc.h:98
int framing_ok_announced
TRUE if framing OK has been announced.
Definition: private/hdlc.h:52
unsigned long int rx_aborts
The number of HDLC aborts received.
Definition: private/hdlc.h:84
Definition: private/hdlc.h:91
int octet_counting_mode
TRUE if in octet counting mode (e.g. for MTP).
Definition: private/hdlc.h:63
int progressive
TRUE if frame creation works in progressive mode.
Definition: private/hdlc.h:102
size_t pos
The current send position within the buffer.
Definition: private/hdlc.h:124
modem_rx_status_func_t status_handler
The callback routine called to report status changes.
Definition: private/hdlc.h:43
int flag_octets
The number of flag octets to send for a timed burst of flags.
Definition: private/hdlc.h:113
int num_bits
The number of bits currently in octets_in_progress.
Definition: private/hdlc.h:109
void * frame_user_data
An opaque parameter passed to the frame callback routine.
Definition: private/hdlc.h:41
int num_bits
The current number of bits in byte_in_progress.
Definition: private/hdlc.h:61
int flags_seen
Number of consecutive flags seen so far.
Definition: private/hdlc.h:54
unsigned long int rx_length_errors
The number of too short and too long frames received.
Definition: private/hdlc.h:82
int report_bad_frames
TRUE if bad frames are to be reported.
Definition: private/hdlc.h:47
int abort_octets
The number of abort octets to send for a timed burst of aborts.
Definition: private/hdlc.h:115
hdlc_frame_handler_t frame_handler
The callback routine called to process each good received frame.
Definition: private/hdlc.h:39
int tx_end
TRUE if transmission should end on buffer underflow .
Definition: private/hdlc.h:134
size_t len
The length of the message in the buffer.
Definition: private/hdlc.h:122
unsigned long int rx_frames
The number of good frames received.
Definition: private/hdlc.h:78
int octet_count
Octet count, to achieve the functionality needed for things like MTP.
Definition: private/hdlc.h:66
hdlc_underflow_handler_t underflow_handler
The callback routine called to indicate transmit underflow.
Definition: private/hdlc.h:96
unsigned long int rx_crc_errors
The number of frames with CRC errors received.
Definition: private/hdlc.h:80
uint8_t buffer[HDLC_MAXFRAME_LEN+4]
The current message being transmitted, with its CRC attached.
Definition: private/hdlc.h:120
unsigned int byte_in_progress
The destuffed bit stream buffer.
Definition: private/hdlc.h:59
unsigned int raw_bit_stream
The raw (stuffed) bit stream buffer.
Definition: private/hdlc.h:57
unsigned long int rx_bytes
The number of bytes of good frames received (CRC not included).
Definition: private/hdlc.h:76
#define HDLC_MAXFRAME_LEN
Definition: hdlc.h:46
uint8_t buffer[HDLC_MAXFRAME_LEN+4]
Buffer for a frame in progress.
Definition: private/hdlc.h:71
uint32_t crc
The running CRC, as data fills the frame buffer.
Definition: private/hdlc.h:126
int octet_count_report_interval
The number of octets to be allowed between octet count reports.
Definition: private/hdlc.h:68
size_t max_frame_len
Maximum permitted frame length.
Definition: private/hdlc.h:37
int idle_octet
The currently rotated state of the flag octet.
Definition: private/hdlc.h:111
Definition: private/hdlc.h:32
size_t len
Length of a frame in progress.
Definition: private/hdlc.h:73
int crc_bytes
Definition: private/hdlc.h:94
int bits
The number of bits remaining in byte.
Definition: private/hdlc.h:131
int report_flag_underflow
TRUE if the next underflow of timed flag octets should be reported.
Definition: private/hdlc.h:117
uint32_t octets_in_progress
The stuffed bit stream being created.
Definition: private/hdlc.h:107